Commit 1fd17cce authored by unknown's avatar unknown

Merge sinisa@work.mysql.com:/home/bk/mysql-4.0

into sinisa.nasamreza.org:/mnt/work/mysql-4.0

parents 2d4e07f2 9b515ad0
...@@ -2702,14 +2702,22 @@ row_search_for_mysql( ...@@ -2702,14 +2702,22 @@ row_search_for_mysql(
unique_search_from_clust_index = TRUE; unique_search_from_clust_index = TRUE;
if (prebuilt->select_lock_type == LOCK_NONE if (trx->mysql_n_tables_locked == 0
&& prebuilt->select_lock_type == LOCK_NONE
&& trx->isolation_level > TRX_ISO_READ_UNCOMMITTED && trx->isolation_level > TRX_ISO_READ_UNCOMMITTED
&& trx->read_view) { && trx->read_view) {
/* This is a SELECT query done as a consistent read, /* This is a SELECT query done as a consistent read,
and the read view has already been allocated: and the read view has already been allocated:
let us try a search shortcut through the hash let us try a search shortcut through the hash
index */ index.
NOTE that we must also test that
mysql_n_tables_locked == 0, because this might
also be INSERT INTO ... SELECT ... or
CREATE TABLE ... SELECT ... . Our algorithm is
NOT prepared to inserts interleaved with the SELECT,
and if we try that, we can deadlock on the adaptive
hash index semaphore! */
if (btr_search_latch.writer != RW_LOCK_NOT_LOCKED) { if (btr_search_latch.writer != RW_LOCK_NOT_LOCKED) {
/* There is an x-latch request: release /* There is an x-latch request: release
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment